Method for utilizing submerged combustion



March 23, 1965 w. G. SEE ETAL METHOD FOR UTILIZING SUBMERGED COMBUSTIONFiled NOV. 13, 1961 S E M Z WEN B EE E W m G V.

w 0 RT 71 ER TE A M O I W R Y B United States Patent 3,174,820 METHODFOR UTILIZING SUBMERGED COMBUSTRON Walter G. See, Qrown Point, andRobert V. Heiuzc, Hammend, lnd., assignors to Submerged CombustionCompany of America, fine, Hammond, End, a corporation of Indiana FiledNov. 13, 19611, Ser. No. 151,2??? 3 (Ilaims. ('Cl. 23-1) This inventionrelates to new and improved process for utilizing submerged combustion.

This application is a continuation-in-part of our cending applicationSer. No. 340,176, filed March 4, 1953, now abandoned.

Submerged combustion burners are known in the art and have been usedvery satisfactorily in heating liquids, as for example, in heatingpickling baths containing sulfuric acid. One of the difiicultiesheretofore encountered in the use of submerged combustion burners whichhas made them inapplicable for many purposes is the very high flametemperature which may be from around 2500 F. to 8000 F., depending uponthe combustible gas used in the burner. For example, where natural gasis used as the fuel, the flame temperature is around 2900 F. Thisemperature is too high to permit the burner to be used directly inheating some types of solutions where the high temperature would producecharting or otherwise have a harmful effect upon the solution beingheated.

One of the objects of the present invention is to provide a new andimproved method and apparatus for utilizing submerged combustion whereinthe flame temperature of the submerged combustion burner is controlled,altered and/ or governed by the introduction of coolants and/orreagents, chemical or otherwise.

Another object of the invention is to provide a new and improvedsubmerged combustion apparatus which is applicable for use in carryingout chemical reactions.

Other objects and advantages of the invention will be apparent byreference to the following description in conjunction with theaccompanying drawings in which:

FIG. 1 represents an elevated view partly in section and with partsbroken away of one form of apparatus suitable for the practice of theinvention;

FIG. 2 represents a modified form of the apparatus illustrated in PEG.1.

The apparatus illustrated in FIG. 1 comprises a cylindrical closed heatexchange chamber 1 containing a submerged combustion burner 2. Acylindrical combustion chamber 3 is provided around the lower end of thesubmerged combustion burner 2 and is surrounded by a shell 4 which isprovided with an inlet 5 near the upper end thereof and walls 6 whichtaper to form an opening 7 in the lower end thereof. The combustionchamber 3 is provided with an opening 8.

The submerged burner 2 is preferably of the type described in See etal., US. Patent 2,118,479. In the type of burner shown, a fuel gas suchas natural gas or other suitable type of fuel gas, is introduced througha main gas conduit 9 and a pilot gas conduit ll). Support for combustionis provided through a main air conduit ll and a pilot air conduit 12.The combustion occurs at the burner plate 13 which is located within thecombustion chamber 3. The operation of the submerged combustion burnercan be controlled automatically in a number of different ways but sincesuch controls do not form a part of the invention they will not bediscussed in detail.

The liquid M which is to be heated is introduced into the heat exchangechamber 1 through conduit 15 controlled by valves 16 and 17. The heatedliquid can, if desired, be circulated to a tank or other vessel throughthe outlet 18 and can be recirculated through the conduit 19,

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provided with check valve 20. A thermometer well 21 is provided in orderto make it possible to determine the temperature of the heated liquid.For specific purposes additional liquids can be added through theconduit 19.

The burner assembly has a shell or manifold 4 to which a suitable gas orvapor is added in order to dilute and reduce the temperature of the hotproducts of combustion issuing from the opening 8 in the chamber 3.Since the manifold d is substantially concentric with respect to thechamber 3, the stream of hot gases issuing from the chamber 3 isvirtually surrounded by a stream of cooler gases or vapors introducedthrough conduit 5 and passing between the inner walls of manifold 4 andthe outer walls of chamber 3. In this way the high temperature of thehot gases of combustion is reduced in a uniform manner and localoverheating as these gases strike the liquid 14 is substantiallyavoided. The submerged combustion apparatus is provided with additionalconduits 22 and 23 (or multiples thereof) which are adapted to conductchemical reagents into the shell or manifold 4 in such a manner thatthey can be sprayed or caused to be brought into contact with each otherthrough nozzles 24 and 25 (or multiples thereof) located most favorablybetween the port of flame 8 and the port of emergence 7.

The apparatus illustrated in FIG. 2 is generally similar to thatillustrated in FIG. 1 and like numerals indicate like parts. Onedifference between the apparatus illustrated in FIG. 1 and thatillustrated in FIG. 2 is the provision of the opening 26 around thecombustion chamoer 3 which permits the liquid to recirculate upwardlythrough the burner assembly and around the outside of the shell 4.Opening 26 may be reduced to a nozzle and may permit release ofrecirculating liquid and gases above or below the material level asoperation may demand.

In operation heat is supplied by the submerged burner 2 which delivershigh temperature flames at point 13 located within the combustionchamber 3 and which in turn empties out into the shell 4. Chemicalswhich it is desired to react are introduced through the conduits 22 and23 or multiples thereof. The intensity of the heat causes these chemicalreagents to be heated to the desired temperatures before emergingthrough the opening 7 Where the resultant gases, vapors, liquids and/orfluids are doused into a body of other chemicals, gases, vapors, liquidsand/ or fluids contained in and/ or being conducted through the heatexchange chamber 1 for positive control of reaction factors. Where it isdesired to control, govern and/or ameliorate the flame temperature adiluting gas or vapor is introduced through the conduit 5. When conduit5 is not used for this purpose it can in some instances be used toremove reaction products by flow in the reverse direction from thatshown by the arrow in the drawing.

The apparatus described can be employed to oxidize sulfur andsulfur-bearing reagents to sulfur trioxide and sulfuric acid. It canalso be used to oxidize and to cause the nitration of organic chemicalsfor the production of derivatives of these chemicals. In particular, itcan be used for the processing of lignite, coal, oil shales, carboxylicacids, petroleum, cyclic compounds derived from petroleum in present dayrefining apparatus and like substances.

Another use for the apparatus is to employ sulfurbearing gases andvapors such as those derived from petroleum as fuel by introducing themthrough the gas conduits 9 and 16 and then absorbing the resultantsulfur dioxide and/or sulfur trioxide in water or other liquids (e.g.,liquids which are to be sulfated or sulfonated), to bring about theformation of sulfuric acid or sulfated or sulfonated organic compounds.In this way it is possible to utilize objectionable sulfur-containingby-products from petroleum refineries for the purpose of making sulfuricacid and other desirable products. It is also possible to supplementand/ or replace present day apparatus for separating sulfuric acid fromacid sludges produced in oil refineries.

It will be recognized that the manifold or shell 4 can have a variety ofshapes with numerous inlets and outlets for accomplishing andcontrolling chemical reactions and changes. Its possibilities areexceedingly flexible.

In a typical installation burning natural gas supplying a B.t.u. valueof 250,000 B.t.u. per hour, 41 cubic feet per minute of air is addedthrough the pilot air and main air inlets of the burner and 180 cubicfeet per minute of auxiliary air is added through conduit 5. Throttlingvalves can be used on the various conduits supplying air and gas to theburner and the conduits supplying auxiliary air in order to control thefuel and air supply as Well as temperature within the desired limits.Either the air or the fuel gas, or both, can be throttled within certainlimits. The pressure of the air and gases must be sufiicient to overcomethe head of solution. Thus, for 60 feet of Water approximately 31 poundsof air and 31 pounds of gas pressure are required to overcome the headof solution and greater pressures are required for solutions having ahigher specific gravity.

It will be understood that suitable control valves and check valves canbe added to the apparatus and that other variations and modificationscan be made Without departing from the invention. Instead of airrelatively pure oxygen, such as tonnage oxygen, can be used to supportthe combustion of the gas in the burner.

The apparatus described can be operated at atmospheric, subatmo'sphericor superatmospheric pressures. If subatmospheric or superatmosphericpressures are used the heat exchange chamber 1 must be pressure-tightand must be provided with suitable pressure release devices.

The invention provides an apparatus comprising a burner having a burnerplate adjacent one end thereof, a combustion chamber around said burnerwith the inside walls of said chamber spaced from the outside walls ofsaid burner and projecting beyond said burner plate in the direction offlame propagation, the projecting end of said combustion chamber havingan opening therein, a shell spaced from the outside walls of saidcombustion chamber forming a passageway around said combustion chamberand projecting beyond said combustion chamber in the direction of flamepropagation, the portion of said shell projecting beyond said burnerplate having an opening therein, and a conduit in said shellcommunicating with said passageway. By introducing air or other suitablegas, coolants, and/or reagents into said last named conduit, the flametemperature can be controlled, altered and/or ameliorated for theintended purpose.

By providing a conduit or multiple conduits communicating with the spacebetween the opening in the combustion chamber and the opening in saidshell or manifold, it is possible to introduce into the zone between theopening in the combustion chamber and the opening in the shell one ormore chemicals capable of reacting with components of the combustiongases or with each other in order to produce chemical compounds whichcan then be conducted to a suitably prepared solvent, diluent or reagentin the heat exchange chamber 1 for removal from the reaction zone. Thus,the invention provides a new method of carrying on chemical reactions.

The invention is hereby claimed as follows:

1. A process of conducting a chemical reaction at a controlledtemperature in a zone heated by hot combustion gases which comprisespropagating from a burner a flame, forming a substantially enclosed,reaction zone beneath the surface of a body of liquid into which the hotcombustion gases flow, introducing into said reaction zone a coolant gasin a quantity sufficient to cool the hot combustion gases in said zoneto a desired reaction temperature, simultaneously introducing into saidreaction zone at least one chemical reactant which reacts in said zoneat the aforesaid reaction temperature, and discharging from said zonethrough a restricted opening therein into said body of liquid saidcombustion gases, coolant gas, and products of reaction in said reactionzone, thereby dousing the discharged mixture in said body of liquid.

2. A process for conducting a chemical reaction at a controlledtemperature in a zone heated by hotcombustion gases which comprisespropagating from a burner a flame, forming a substantially enclosed,reaction zone beneath the surface of a body of liquid, flowing hotcombustion gases from said flame through said zone, introducing intosaid reaction zone a fluid to regulate the tempenature in said reactionzone at the desired reaction temperature, simultaneously introducinginto said reaction zone at least one chemical reactant which reacts insaid zone at the aforesaid reaction temperature, and discharging fromsaid reaction zone through a restricted opening therein, along with saidcombustion gases, the products of reaction into said body of liquid,thereby dousing the discharged mixture in said body of liquid.

3. A process as claimed in claim 2 wherein said flame is propagated fromsaid burner within an enclosed combustion zone located within saidreaction zone and opening in the direction of flame propagation intosaid reaction zone.

References Cited in the file of this patent UNITED STATES PATENTS1,798,785 Canter Mar. 31, 1931 1,871,108 Burnett Aug. 9, 1932 2,174,533See et al Oct. 3,1939 2,519,481 Kubie et al Aug. 22, 1950 2,590,436Luten Mar. 25, 1952 2,643,938 Robinson June 30, 1953 2,723,659 Young etal Nov. 15, 1955 2,787,318 Wolfersperger Apr. 2, 1957 3,056,467 RavichOct. 2, 1962 3,060,005 Litchfield Oct. 23, 1962.

1. A PROCESS OF CONDUCTING A CHEMICAL REACTION AT A CONTROLLEDTEMPERATURE IN A ZONE HEATED BY HOT COMBUSTION GASES WHICH COMPRISESPROPAGATING FROM A BURNER A FLAME, FORMING A SUBSTANTIALLY ENCLOSED,REACTION ZONE BENEATH THE SURFACE OF A BODY OF LIQUID INTO WHICH THE HOTCOMBUSTION GASES FLOW, INTRODUCING INTO SAID REACTION ZONE A COOLANT GASIN A QUANTITY SUFFICIENT TO COOL THE HOT COMBUSITON GASES IN SAID ZONETO A DESIRED REACTION TEMPERATURE, SIMULTANEOUSLY INTRODUCING INTO SAIDREACTION ZONE AT LEAST ONE CHEMICAL REACTANT WHICH REACTS IN SAID ZONEAT THE AFORESAID RECTION TEMPERATURE, AND DISCHARG-